Written in the Stars
by loonyl52
Summary: After a muggle uncovers a family secret, two bitter and lonely people must learn to coexist in Grimmauld Place. OOTP AU
1. Chapter 1

Not for the first time, an argument had broken out at Number Four, Privet Drive, complete with shouting, a slam of the patio door, and a profusely red-faced Vernon Dursley.

However, this may well have been the first time said argument had nothing to do with the Dursleys' infamous nephew, Harry Potter, whose presence was known to ignite more than a few altercations in the last fourteen years.

This cloudy Tuesday morning was consequently a welcome change for Harry, who felt perfectly content to sit, concealed behind the bushes, and listen to the exchange unfolding on his uncle's doorstep.

"If your rhinoceros of a son tries to pull another stunt like that, I will have no qualms about flattening that bloody BB gun with my car!"

"How _dare_ you threaten my son? I have nothing left to say to you. Get off of my property before I call the police!"

"I _am_ the police, you daft idiot. So, tell that boy to stay the hell away," snarled the woman who had marched up to the Dursley's home minutes before, interrupting the news broadcast with three loud, sharp knocks.

"They told me this was a _nice_ neighborhood," she huffed as she crossed the street back over to Mrs. Figg's house. Harry reflected that, all things considered, it could have gone worse. At least the new neighbor realized that arguing with Uncle Vernon was a hopeless case, despite her completely reasonable justification.

The crash that rattled the street in the middle of breakfast originated when Dudley had the brilliant idea to test out his birthday present, a top-notch BB gun, on poor old Mrs. Figg's window.

It was a sound plan at first, seeing as Mrs. Figg, with her bad leg, would never have reached her shattered window in time to see Dudley's friends running down the road and out of sight. However, they had failed to take into account that Mrs. Figg had a visitor whose ability to detect trouble rivaled Aunt Petunia's.

Harry heard Uncle Vernon return to the living room, grumbling about nosy degenerates as he presumably retook his seat by the television.

"Don't worry, Dudders, she won't pester us again. Just some busybody who came out of nowhere and can't mind her own damn business," he reassured.

"Must be the niece Mrs. Figg was telling me about," Aunt Petunia's voice drifted from the kitchen. "She won't be here more than a week, as far as I know."

 _Lucky her_ , Harry thought as he stared at the clouds overhead, trying to erase the miserable reminder that he would remain stuck on Privet Drive for the next two months.

* * *

The hours passed quietly and without any indication that an incident had taken place. Once again bored and frustrated out of his mind, Harry found himself kicking pebbles scattered around a street that he could only remember venturing to on one previous occasion. There was a playground ahead, empty now that the sun was beginning to set, and what looked like an abandoned tunnel standing in the middle of the path. Harry's thoughts had carried him to the outskirts of Little Whinging, but at least no one would care if he was gone for a while.

Unfortunately, this time it seemed that someone _had_ noticed his absence, as proven by a snide "Where'd you think you're going, Potter?"

Harry didn't even have to turn around to know who it was: Dudley's gang, who he somehow managed to encounter in the most unlikely of places at a time when there was no one else around.

"I _said_ ," sneered Dudley. "Where're you going? Haven't seen you 'round lately. You hiding from us?"

There was never a chance of avoiding his cousin, but Harry remained silent, his hand instinctively moving closer to the wand in his back pocket.

"You scared? Must be why you're always crying and screaming at night…"

* * *

"Follow the boy, Erin. Don't let him out of your sight," her senile aunt had told her.

Her incredulous response: "The one who put a bullet in your window? Can't imagine that will go over well. I can drive you to the station to file a report in the morning."

"Don't be silly, I meant the Potter boy. He's been hiding in the Dursleys' yard all day, and now he's set off. Don't tell me he isn't up to something."

"C'mon, Auntie. As if I have nothing better to do."

But she didn't have anything better to do, and her aunt knew it.

Trailing the boy wasn't especially difficult, even though she still had no idea why it was necessary in the first place. There was only one road in and out of Little Whinging, so as long as she kept a reasonable distance, there was no reason to alert Potter's suspicions.

Erin wasn't exactly the police, as she had so proudly declared earlier. Certainly not anymore. But the training hadn't been for nothing, although she always imagined putting it to better use than keeping tabs on a teenager who, by all accounts, had been minding his own business.

But apparently, trouble didn't need an excuse to find this boy, and trouble took the form of three rather menacing figures, one of which Erin grudgingly recognized. _Wonderful_.

Sure enough, there was Dudley (who made quite a name for himself in the neighborhood, as Erin already heard in her brief visit) carrying his prized weapon.

The ringleader said something to Potter that Erin couldn't hear from her convenient, though admittingly undignified, hiding spot behind a dumpster, but she did notice Potter reaching for something behind his jacket, and she was _not_ going to stay in this godforsaken town any longer than planned just to give her statement as a murder witness.

* * *

"Alright, that's enough," A voice that Harry immediately recalled emerged as its owner came into view: a woman who he had never seen before, approaching the scene in quick strides until she was standing in between him and Dudley.

"I don't want to hear any more shots fired today, 'kay? Whatever this is can wait until I am far, far away from here, but for now, why don't we all make nice and go home?"

Dudley refocused his attention as he took a step closer.

"You think I'm scared of _you_?"

To her credit, the woman didn't flinch as she was glared at like a bug about to be squashed, although she kept her eyes on both Harry and Dudley.

"I don't want to tase you, but you can bet I won't regret it if I do," she replied warily.

Dudley sneered and was about to respond when he felt it. He must have, because Erin did too. A sudden and overwhelming sense of dread that pierced her very soul and made her feel as though she had plunged through a sheet of ice.

She barely had time to register the sensation as abnormal for a warm July day when the clouds began to close in around them, and the darkness that had overcome her senses was reflected by the pitch-black sky.

Dudley's cronies ran off, but he remained still.

"Stop that! Make it stop!"

He bellowed at the other boy, who was silently scanning his vicinity as though the person responsible would suddenly appear.

Bewildered, Erin was about to ask what the hell was going on, when Potter spoke for the first time, whispering more to himself than to the others.

"What are they doing here?"

"If you don't quit it, I'll…"

"Shut up!"

He screamed at Dudley, who had raised his fists as if punching the air could make the cold disappear.

But it was not just the cold, Erin realized. There was something else happening, something that she couldn't and had no desire to explain. She turned to face Potter, who had backed away and was cautiously approaching the tunnel. Erin saw the beam of a flashlight over his retreating back. He had barely taken a few steps when he suddenly turned around and bellowed.

"Run!"

The command turned to lead in Erin's brain, as she felt darkness envelop her and the street blur from her view…

Replaced with something far worse than the frigid atmosphere. The questions that should have been irrevocably erased from her memory, echoing through and consuming her pounding head.

… _make things so difficult, Erin?_

… _we promised, didn't we?_

… _do you know why you're here?_

And suddenly, the voices stopped as soon as they had come. And there was no more darkness, but the scene before her eyes wasn't a much better sight.

* * *

One boy was lying sprawled on the grass, and the other had crouched down beside her. She became dimly aware that she was no longer standing, but had bent over to keep her shaking knees from giving way under her.

"Are you alright?" He asked cautiously, glancing over at Dudley before returning his attention to her.

Taking what felt like her first breath in ages, Erin replied hoarsely,

"Not sure. What happened to me?"

She could see him hesitate before answering.

"It's better if I explain later. Right now, trust me, we have to get out of here. I'll get Dudley up, but we've got to start walking. Can you do that?"

Not knowing what else to do, Erin nodded and, after taking a tentative step to ascertain that she wouldn't immediately fall over, picked up her pace to reach the two boys. With difficulty, one heaved the other up and struggled to support his weight. Erin took his other arm, receiving no response from a seemingly unconscious Dudley.

* * *

The walk back to Privet Drive was slow and agonizing, and Erin could feel her entire body aching from the strain. The effort left no energy to think, but seeing the familiar street completely deserted aside from the chirping of crickets in the distance reminded her where she had been for hours.

"I'll listen to that explanation anytime now," she muttered, looking up at Harry for the first time since they left. "Starting with who you are, if you don't mind."

Under the streetlights, Harry was able to see the woman clearly for the first time. She was wearing jeans and sneakers, leaving no doubt that she was a muggle. He decided there was no point in lying to her.

"I'm Harry Potter. I live with the Dursleys, but I think you've already met them. This is my cousin, Dudley."

The easiest question was answered, but Harry was no closer to finding a convincing way to explain the events that had transpired, when he hardly knew the truth himself.

"Thanks for stepping in, by the way, but can I ask you something: what were you doing on Magnolia Crescent?"

"Keeping an eye on you," she replied with a tight smile. "Well, following you, really. Take it up with my aunt…uh, Mrs. Figg, if you want to know why, because all she told me was that you were up to something. Anyway, I guess if I know your name, it's only fair that you know mine. I'm Erin Mills, and dying to know exactly what happened back on…what was it? Magnolia Crescent."

Another moment of silence followed as Erin realized that they had arrived at her driveway.

"Look, I really am sorry about everything. But I'm still trying to piece that part together, and I know you're probably not feeling too good right now. The best thing you can do is get some rest, and I swear I'll tell you everything when I can."

At any other time, Erin would have aggressively pressed for answers, but as Harry Potter looked almost as exhausted and confused as she felt, and she knew that there would be none tonight. Besides, her desire to sleep and get rid of the sense of misery that had lodged itself into her gut convinced her to release Dudley and return home without a word of protest.

She barely managed to close the door behind her before she collapsed into a heap on the kitchen floor.

* * *

 **Author's Note**

I don't own _Harry Potter_.

Any comments and feedback would be greatly appreciated, and Chapter 2 will hopefully be up in a few days!


	2. Chapter 2

The first thing Erin registered as she woke was a headache no amount of aspirin would be able to cure, and she kept her eyes tightly shut as her nails dug into the mattress.

The knowledge that she had spent the night in her bed and not on the kitchen floor filled her with a rare and overwhelming sense of gratitude towards her aunt, which was soon replaced with an unsettling sensation whose cause she could not pinpoint at the moment.

Gritting her teeth, Erin began to push herself into a sitting position, when a voice admonished her.

"Don't get up just yet, dear. We wouldn't want you to black out again, would we?"

Erin froze.

Her aunt wasn't there, and she didn't know who was. Forcing her eyes open, she began to suspect that this was not her bedroom, either.

The first thing her blurred vision focused on was the red-haired woman peering over her with a concerned expression.

Words failed Erin as her groggy brain reasoned that another round of sleep would put everything to right, and she closed her eyes just in time to feel a pleasant cooling sensation eliminate the throbbing pressure between her eyes.

Frantically, she opened her eyes again, suppressing a groan when the strange room and person hovering over her did not fade away.

"It's perfectly normal to feel a slight twinge. We didn't want to startle you while you were unconscious last night, but now that you're awake, I can get the others in here," the woman continued, oblivious to the panic bubbling through Erin. "They can explain everything if you'll just wait…"

But Erin heard no more, as her senses finally began to catch up to her racing mind, and she sprung out of the bed and darted out the ajar door.

She stumbled through the hallway like a blind person, clawing at the wall for support until it vanished and she managed to gracefully stumble down a set of stairs.

* * *

Hearing several sets of footsteps hurriedly approaching, Erin racked her brain for every horror movie she had ever watched, wondering if any of them contained useful strategies for escaping the abductor's house.

Shaking loose strands of hair away from her face, but making no move to stand, she looked up to see a hand hovering over her uncertainly.

"We won't hurt you," assured the man whose face she couldn't see at the moment.

 _Definitely something a serial killer would say._

It was only then that she felt another sharp pain shoot through her hip, and as the absence of the familiar weight of the taser holster underneath under her hoodie became apparent, she wearily decided to play along.

Allowing the hand to pull her up to her feet, she saw at least half a dozen people staring at her, one of whom she recognized as the red-haired woman. The others quickly shuffled aside to let whoever had helped her up lead her away from the staircase, urging her to sit down as soon as they entered a room almost completely occupied by a long dining table.

Her abductors filled the remaining seats, none taking their eyes off of her, and she saw the person sitting beside her ask softly,

"How are you feeling, Miss Mills?"

Erin immediately noticed a long, jagged scar running across the man's face, but he did not appear overtly threatening, waiting patiently for a response.

An honest answer died in her throat as his words began to sink in.

"You know who I am?" she whispered.

"Yes, Harry told us last night. I suppose you can say I'm a family friend, though I admit that I never knew Arabella had a niece."

He continued, oblivious to the alarm that must have clearly etched itself onto her face.

"I can assure you, Miss Mills, that you are in no danger. Not from us, at least. Tell me, has your aunt ever mentioned her affiliation with the Order of the Phoenix?"

He said all of this so calmly that Erin momentarily forgot who the insane party was, and slowly shook her head to convey that she had no idea what he was talking about.

"I expected as much. I understand that this must all seem incredibly confusing to you, but I'm afraid this is going to be a rather difficult story to tell."

Her voice instantly returned, though not without its customarily caustic edge as she scoffed, "I have a feeling that I won't be going anywhere anytime soon, so I think it would be best to just rip off the band-aid, if you know what I mean."

"Of course," the man smiled, unperturbed. "Please believe that we had every intention of relaying this information, though preferably once you had more fully recovered from the shock. But now that you're here, why don't we begin with introductions? My name is Remus Lupin. But please, call me Remus. And this is Mad-Eye Moody, Kingsley Shacklebolt, Arthur and Molly Weasley, Sirius Black, and Nymphadora Tonks."

" _Just Tonks, Remus_ ," A younger woman with bright pink hair huffed, but Remus continued to point each person out in turn, as if knowing their names would prevent them from killing Erin. If anything, her knowing who they were made them even _more_ likely to kill her.

Yes, it all made perfect sense now. She was going to die in a strange house filled with crazy people, possibly in this very room. Although why they had decided on her remained a mystery. As far as she knew, she had been on her best behavior as of late. Surely whatever she had said to that awful neighbor the other morning wouldn't warrant such an extreme response.

Until that point, she had all but forgotten the rather memorable event that had transpired on Magnolia Crescent, but if _Harry_ had told them who she was…

"Does that kid have something to do with this? Did he tell you where I live?" She interrupted whatever Remus was about to say next.

"Yes, Harry was very worried about you," the man Remus had introduced as Kingsley Shacklebolt spoke up. "And so were we, when we found you. Arabella agreed that it was best for bring you back here before you sustained any lasting damage."

"Auntie was alright with this? Then, you didn't take me here to murder me?"

Erin said incredulously, discerning the meaning between a jumble of words she had never heard before. They seemed genuinely convinced that they had rescued her: a slight relief that, however reassuring, brought her no closer to letting her guard down.

Remus' eyes widened in surprise.

"No, of course not! We would not have taken you from your home if there was any other way to keep you safe. I know how hard this must be, but before I explain further, I must ask you to tell us exactly what happened to you last night. I believe you understand my meaning; not necessary what you saw, but how you felt during the ordeal. It is crucial not to leave out any details, no matter how…implausible…they may seem."

Erin had not been expecting that, but no matter how many times she had replayed the ordeal in her head, she was no closer to making sense of it on her own. Her first logical instinct was not to reveal the truth to a group of strangers who, despite their stated intentions, had pointedly kidnapped her. But she ultimately decided that they probably wouldn't believe her either way. No one would, so she might as well get it over with. She began:

"Everything went cold and dark, and I felt…awful, like I was going to be sick. Then I heard voices that were too far away, but they weren't, really, because they were inside my head. And before you ask, that doesn't happen normally! They were memories that I…I haven't thought about in years, coming back stronger than ever."

She took a shaky breath and continued.

"When I opened my eyes, the boy, erm, Harry, was there, and he told me something was wrong, and we had to get out of there. So, we got his cousin up off the ground and started walking. I made it as far as my house before everything became dark again. Well, there you have it. I know you must think I'm a lunatic. Don't deny it."

She scanned the room, daring one of them to call her story out.

"You're not a lunatic, Miss Mills. You're just as sane as we are," Remus said kindly.

 _Not exactly reassuring_ , Erin thought darkly, taking in for the first time the appearance of her "rescuers" and noting they each seemed to be wearing what could only be described as an elaborate black poncho. It did not help, nor did it escape her notice, that one of the men had a false eye that had not stopping spinning, or that the younger woman ( _Tonks_ , she recalled) had somehow transformed her hair into a dark maroon midway through Erin's speech.

"It's just as Harry said," Remus continued. "You were attacked by dementors."

* * *

Erin was about to ask exactly who that was, when the dark-haired man sitting in the corner of the room snapped impatiently at Remus.

"Look, Moony, she clearly has no idea what you're talking about, and we don't have time for this. Why can't we just obliviate her and get on with our lives? The Order has enough to worry about as it is."

"That may well be, Black, but as it stands, her memory is Potter's best defense," the man with the strange eye growled. "We need it intact for the trial."

"You don't really think they'll believe a muggle's story…"

"Right now, she's the only witness we've got. Obliviating her would destroy any credibility in Potter's case, which is exactly what the Ministry would want."

"If you lot are going to tell me anything at all, I want to know what this Order is you keep mentioning," Erin snapped before Black could reply, remembering Remus' earlier question.

There was a brief silence, before Kingsley Shacklebolt said evenly.

"Dark forces threaten to overtake your world, Miss Mills. Albus Dumbledore founded the Order to combat…"

The grave implications were lost on Erin as she abruptly let out a loud, hollow laugh.

"Hold on, you can't mean… _Albus Dumbledore_? The sorcerer who runs a school in a magical castle? I knew Granny was off her rocker when she made those stories up. But I guess she wasn't the only one."

She said the last part mostly to herself, as she recalled the first time she had heard that name. The story had become something of a family tradition, begun by her old and somewhat senile grandmother, who enjoyed nothing more than spinning tales of an elaborate world of witches and wizards and all sorts of fantastical creatures. Her parents did not discourage the stories, assured that they were as harmless as any fairy tale. Albus Dumbledore was a name that often surfaced, described by Granny as the greatest and most powerful sorcerer of all time.

 _Will I ever meet him, Granny?_

 _Perhaps one day, my dear child. He invites all of the special children to his school to teach them magic. You never know; you could be one of them._

She certainly didn't feel very special as she tried to recall whether Granny had ever mentioned the existence of a mysterious Order in this magical world, that kidnapped the naughty children and imprisoned them in dark, labyrinthine houses.

She must have zoned out, because Remus was watching her as though _she_ was the crazy one.

"Is _that_ what this is all about? I thought they were stories. Children's stories, you know. About the bearded wizard who fought evil."

For some incomprehensible reason, Remus actually looked relieved.

"Well, at least that's one less thing to explain. I suppose we should be grateful that your grandmother was a bit lax in her observance of the International Stature of Wizarding Secrecy. Tell me, is there any way to convince you that these children's stories, as you call them, are true?"

And then she began to wonder if she was insane, after all.

* * *

The unsophisticated snort that escaped her mouth conveyed her answer, as Remus smiled wearily.

 _Did anything unsettle this man?_

"I don't blame you. Nevertheless, there is indeed a wizarding world which we, and now you as well, are a part of. Obviously, I don't expect you to take my word for it."

Before Erin could decide if that was his idea of an ironically veiled threat, he seemingly extracted a wooden stick out of thin air, and waved it in her direction. She was about to shriek in protest, when he merely pointed the stick at an empty glass standing on the table beside her. Her eyes widened as it instantly began to refill itself with water.

"Drink this, you look on the verge of passing out again," he suggested, offering the cup, which Erin took warily and drained, praying that it really was water.

 _Parlor tricks_ , she decided.

"Are you going to convince me I'm a witch?" she asked disbelievingly. "Is that what you told my auntie last night? Because even she can't be daft enough to believe that."

"You are not a witch, Miss Mills, although my guess is that your grandmother was. It makes sense; Arabella Figg is a squib. A person born with no magic abilities, more commonly known as a muggle, with at least one magical parent. She has been a valuable asset to the Order, nevertheless."

"Let's just hope she hasn't been spilling our secrets as freely as her mum," Mad-Eye Moody muttered under his breath.

Remus continued as though no one had spoken.

"You have every reason not to believe me, but I think that deep down, you do. But what really matters is this: last night, something inexplicable happened to you, for no reason other than the simple fact that you were in the wrong place at the wrong time. You were attacked by the darkest and most dangerous creatures known to wizard-kind. Harry managed to fend them off, but although you fared better than young Mr. Dursley, muggles are not meant to withstand the dementors' effects. Harry told us everything when we arrived to retrieve him that night, and we decided that the best way to ensure your protection was to bring you to London with us. You gave Arabella quite a fright, but she knows that you are safe. And you are; I swear that we mean you no harm."

Erin had never heard a more bizarre speech in her life. She tried to detect a smile as she scanned the room again, trying to find some indication that this was all an elaborate joke. Maybe there was a hidden camera somewhere. That thought, combined with sheer curiosity, made her decide to give that theory one more go.

"If you lot are wizards, can you, you know…"

She made a slight swishing motion with her hand, purposefully eyeing the wand that was now laying idly on the table. It was not Remus who complied, but Sirius Black, who rose from his chair with a flourish and promptly vanished with a loud _crack_ , only to be replaced by a large black dog, flashing Erin a purposeful and triumphant glare.

It took every ounce of her self-control not to scream, as her flippancy and skepticism was replaced by a terror arguably worse than whatever she had felt the day before.

"Do you believe us now, _Miss Mills_?" Sirius challenged as he transformed back.

When she turned to face Remus again, he looked completely unalarmed, though a vague hint of annoyance flickered across his face.

"I still haven't decided that this isn't a dream," Erin said slowly.

He nodded.

"I suppose that's the best we can hope for at the moment."

"Well, if that's all, I think I'll go home and have a nice long drink while I try to process whatever just happened. Did you say we were in London? Terrific, you don't even need to give me a ride. Just show me the door and I'll be out of your way."

As she began to stand, she noticed the rest of the room eyeing her warily.

"Sorry, love, didn't you hear what Mad-Eye said? You're not going anywhere," Sirius Black replied, with a look that made it clear he wasn't any happier about it than she was.

* * *

In all honesty, Erin completely forgot what Mad-Eye had said. She supposed it was lost somewhere underneath the fact that her sweet, harmless grandmother had once been part of a network of wizards. The same wizards that her aunt had _willingly allowed to haul her unconscious body to London_.

She inwardly cursed her decision to come to Surrey in the first place. She could have spent the weekend alone in her flat, blissfully unaware of magic and dementors and whatever the Order had planned for her, which she knew for certain she wanted no part in.

"What are you talking about? There's no reason to keep me here. _None_. You can't possibly think I would tell anyone about this," she spluttered. "I mean, if I don't even believe it, I doubt any…"

"But there is a reason," Arthur Weasley interrupted, speaking for the first time as he looked at Erin with something akin to pity. "And I think you've nailed the problem. As it stands, it's considered a serious offense for a wizard of Harry's age to perform magic, unless warranted by a dire threat. Our Ministry seeks to try and convict Harry because they don't believe the threat was present to begin with."

"And we cannot allow that to happen," Kingsley Shacklebolt added firmly. "Harry Potter is crucial to the success of our mission. We believe that the Ministry is conducting this trial as a front, in order to discredit a far graver danger approaching as we speak."

"The details are, for the time being, irrelevant," said Remus. "But the last thing the Ministry wants is a witness to corroborate Harry's story. If you leave, they _will_ track you down and do everything in their power to silence you, through any means necessary. Sirius is right, Miss Mills. You must remain in Grimmauld Place until you can testify at Harry's trial. We wouldn't do this if there was any other way, but we need your testimony. The fates of our worlds are at stake."


End file.
